Get total number from multiple post object fields

I'm pretty new to PHP so my question might have a very simple answer, but I've searched the ACF forum and Google with no luck. Hopefully someone here can help.

I have four multi-select post object fields on my page and I'm attempting to get the total number of posts (or in my case staff) in those post objects. I'd like to combine them somehow so I can use the total with a conditional.

As mentioned above, this is based on both of hube2's recommendations except that I'm using count() inside my is_array() validations rather than outside of them. Using count() to add the totals together outside the validation was returning a '1' even if the array was empty. So if all of my arrays were empty, I was still getting '4'. I'm not entirely sure why.

There might be a better way to do this, but this is working well for me.

Thanks for the help!

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